Variable speed gear transmission



Nov; 23, 1937. 0. 0. HALL 2,099,734

VARIABLE SPEED GEAR TRANSMISSION Filed-May 25, 1935 '3 Sheets-Sheet 1 Nov. 23, 1937. c o. HALL ,73

VARIABLE SPEEIS GEAR TRANSMISSION Filed May 25, 1935 3 Sheets-Sheet 2 Nov. 23, 1937. v c. o. HALL 2,099,734

VARIABLE SPEED- GEAR TRANSMISSION Filed May 25, 1935 ssheets-sheet s Fatented Nov. 2 3, 1937 I 1 Claim.

The invention relates to improvements in gear transmissions and more specifically to enclosed gear type speed changing transmissions of vari-' ous types, such as planetary, non-planetary, and gyrating gears, in all of which types the output shaft is caused to rotate by reason of the torque reaction of a stationary member or members, such as internal gears, planetv plates, gears which do not rotate on their own axis,.torque arms, etc., and wherein the input shaft is caused to turn at a certain speed by means of some external source of power, which velocity is reduced or increased at a predetermined ratio of intermediate gears to'a relatively lower or higher velocity of the output shaft.

An object of the invention is to produce a gear transmission wherein the output shaft is caused to rotate at various speeds.

Another object of the invention is to produce a gear transmission of compact and rugged construction wherein the output shaft speed may be varied and regulated without a multiplicity of gears and the customary necessity of shifting from one engagement of gears to another in order to procure a change of speed of the output shaft.

A more specific object of the invention is to produce a gear type, variable speed transmitter wherein the speed of the input shaft as well as the speeds of all the intermediate gears are caused to rotate by the rotation of the input shaft at constant speeds, but the velocity of the output shaft is varied by providing means for rotating the torque reaction member in the rotational direction of the impressed torque.

Still another object of the invention is to provide definite control of the velocity of the torque reaction member, thus regulating the velocity of the output shaft by reducing its speed below its normal speed by the exact number of revolutions at which the torque reaction member is caused or allowed to turn. I

The accompanying drawings illustrate one form of the invention, serving to illustrate the structure, principle and method of operation thereof by various views of the same construction wherein the same characters of reference indicate corresponding parts in all views.

Figure 1 is a central vertical section of the transmission at right angles to the input and output shafts.

Figure 2 is a central vertical section on lines AA, facing the inside end of the planet plate and driven members parallel tothe shafts.

Figure 3 is a central vertical section on lines 13-13, facing the inside end of the driving shaft and the driving and driven assembly of the speed changing mechanism.

Figure 4 is a top sectional view on lines C-C.

Referring now more particularly to Figure l for a detailed description of the invention, I des- (Cl. id-285) ignates the external housing of the transmission, 2 the input shaft carried by bearings 3 and 4, 5 the flanged output shaft running in bearing 6 and guided by bearing 6. This shaft is flanged to support the planet gears l which run on shafts 8 in bearings 9, said flange being secured to planet plate I I running in bearing 52 by bolts ill.

Pinion I3 is secured to or cut in shaft 2 and actuates gears I, which causes the planet plate .H to rotate planetarily by reason of the torque reaction of the internal gear M with which planet gears I also engage, thus causing the rotation of the flanged output shaft 5.

The internal gear M is secured by bolts I5 to a spoked or webbed serrated ring or worm gear l6 which either runs in or is supported stationary as desired by bearing ll. I8, is a continuous thread screw cut key or worm which either prevents worm gear Hi from rotating or causes it to rotate or unwind in the rotational direction-of the direct torque impressed on said worm gear by planet gears l through internal gear l4.

Worm I8 is secured to cross shaft l9 carried by bearings 20, and said shaft protrudes through housing I into chamber 2| formed by auxiliary housing 22. To this shaft is also secured driven friction disc 23.

Adjacent to and right angularly contactable with disc 23 is driving disc 24 secured to shaft 25 which is splined or slidably keyed within hollow shaft 26 and journalled in bearing 21.

Within auxiliary housing 28 is hearing 23 which carries hollow shaft 26, to which is secured driven sprocket 38. 31 is a driving sprocket secured to shaft 2, and 32 is a chain connecting sprockets 3 land 30 through apertures 33 in housing 28 and apertures 34 in bearing support 35.

Referring now to Figure 1, 36 designates a lever arm pivoted at 31-, 33 a pin protruding vertically downward from lever 36 and engaging circular key seat 39 in shaft 25. 4D is a handle secured to lever 36, by means of which lever 36 may be swung on pivot 31, thus engaging disc 24 with driven disc 23 at various radii of disc 23, causing said disc to rotate at various speeds.

Referring again more particularly to Figure 2 to trace the direction of rotation of the transmission members, shaft 2 is rotated clockwise facing the outer end, as indicated by the arrow,

ing the back of said disc.

Referring again to Figure 2, worm l8, being pinion II and gears 1 to the planet plate H and flanged output shaft 5 by means of ,the torque reaction of internal gear l4 as long as the internal gear remains stationary or rotates at a velocity of lesser value than the speed of planet plate II. It will also be readily seen that any rotation imparted to internal gear I4 or any recession from its stationary reactive state which is permitted will have direct effect on the speed of rotation of output shaft 5. If the internal gear is caused or allowed to turn at the same speed as that of the planet plate ll, there will naturally be no turning effort transmitted to the output shaft 5.

Referring again to Figure 2, it will be seen that when the transmission is operated in direction of rotation described worm gear It will exert a thrust effort on worm i8 which will cause the worm and worm shaft assembly to move toward driving disk 24 thus creating pressure between sad disc and driven disc 23 and effecting proper trwtion; however if the direction of rotation of the transmission isreversed it will be seen that the thrust tendency of the worm shaft assembly will be in the-opposite direction and there will be no traction between said discs 23 and 24.

I have therefore provided means for adjusting the thrust motion of the worm shaft assembly by leaving space between worm hub 42 and bearing 20 and also between spacer 43 and the opposite bearing 20.

44 is a square milled projection on the endof shaft is and 45 is a machined disc with a square aperture to fit over the projection 44. Said disc is secured to shaft It by screws 46 and has a coned surface on,.the side adjacent to the round section of shaft l9. The opposite face is flat except for a center indenture which provides a seat for a single ball thrust bearing 48.

Around disc 45 is assembled sectional flange 41 which has an inside coned surface positioned adjacent to the coned face of disc 45 and also a flat face with a central ball indenture adjacent to the flat face of disc 45.

Flange or spider 41 is of such outer contour that it cannot turn in similarly contoured aperture 49 but maybe moved laterally in the direction parallel to shaft i9. Integral with said spider is threaded stud 50 which extends through. section 5! of housing I and is fitted with internally threaded hand-wheel 52. Section 5| is removable.

53 is a flange on hand-wheel 52 having its inner face adjacent to and bearing against section 5| andits outer face bearing against the inner face of sectional, shouldered flange 54. Said flange 54 is secured to section 5| and housing -I by bolts 55.

' rection when facing itsouter side it will be seen that coned-surfaces 45 and 41 engage and exert a lateral pull on shaft assembly i9, which will disengage driven disc 23 from contact with disc 24 and also have ,a brake effect on the rotation of shaft l9.

By turning hand-wheel 52 in a counter-clockwise direction it will be seen that said worm shaft assembly is willbe moved toward driving disc 24 and driving traction will be eifected between discs 23 and 24. i

This adjustable thrust feature is also, in ef feet, a clutch, which permits the free adjust-' ment of driving disc shaft 25 forward and back in hollow shaft 26 so that driving disc 24 may be caused to contact driven disc 23 at any desired radius, while the transmission. is either running or idle.

51 is anoil chamber, 58 indicating the oil con tained therein to such a level as will immerse the lower portion of the intermediate transmission and 56 represents oil seals at the various apertures through which the driving and driven shafts protrude. by compounding the mechanism of this transmission, any desired ratio of speed variation may be accomplished.

It will be understood the embodiment of the invention disclosed herein'isillustrative but not restrictive and that various changes in form,

construction and arrangement may be made It will also readily be seen that v within the intention and scope of the following claim.

What I claim is:

A power transmission construction combining an input shaft, a pinion attached thereto, a gear assembly, a torque reaction member havinga worm gear secured thereto, a separate transmission for driving a hollow countershaft from the input shaft, a driven flanged output shaft, an oil containing housing to enclose all these parts, having oil seals at the apertures through which the shafts protrude, adriving friction disc on a slidably keyed shaft within the said countershaft and rotated thereby, a driven disc on another shaft positioned right angularly to said countershaft having the driven disc contactable with the driving disc, a wormsecured to said right-angle shaft which engages the worm gear attached to and of larger diameter than the torque reaction member whereby rotative motion is transmitted to the torque reaction member, a separate housingvapplied securely to the oil containing housing, providing a protective chamber for the friction mechanism, means for adjusting the driving friction disc forward and back acrossthe face of the driven disc from its periphery to a position relatively nearer its axis, a pivoted lever having a handle, a pin through said lever positioned to engage a circular keyway in the driving disc shaft, to engage the driving disc with the driven disc at various radii of the driven disc.

- CHARLES C. HALL. 

